4.5. What is an acceptable level of risk?
In a general way, the question of what is an acceptable level of risk in road traffic is virtually impossible to answer. Any limit other than zero risk is arbitrary and disputable. Zero risk, however, may be a valid ambition in theory, but hardly possible, if at all, to realise in practice. Furthermore, when talking about the acceptable level of risk a distinction must be made between various types of risk, for example individual risk versus societal risk and voluntary risk versus compulsory risk. What risk level is acceptable for an individual road user when he or she makes a particular trip with a particular transport mode? What is the acceptable risk level for society as a whole, in other words how many accidents or casualties per year per unit of exposure are we as a society willing to accept at public roads? And is it reasonable to accept higher risks when these are taken on a voluntary basis (e.g. a recreational bicycle tour) than when taken on a compulsory basis
(e.g. for professional drivers or home-work travel). Some of these questions are answered by society, through actions that government and local agencies take on the programs and budgets devoted to road safety. There are no absolute and correct levels, as becomes obvious when looking at the actions taken in different countries, which result in them having different levels of risk and safety. At the individual level there are also no correct and absolute answers. Individual risk varies from person to person, from task to task and can even vary for the same person depending on mood, timepressure
and whether the risk is voluntary or compulsory.